This invention relates to a combination switch provided in the vicinity of a handle column for controlling turn lamps, wipers and so on.
One known combination switch of the type described is shown in FIGS. 1 to 3. FIG. 1 is a cross-sectional view of the conventional combination switch in a direction of a steering shaft, FIG. 2 is an enlarged view of a body portion, and FIG. 3 is a view as seen in a direction of arrows A of FIG. 2. The combination switch 1 comprises a body 3 through which the steering shaft extends, a turn lever switch 5 for operating head lamps and turn lamps, a wiper lever switch 7 for operating wipers and a washer, and a control unit 9 having a control circuit.
The body 3 includes a steering shaft insertion portion 11 (see FIG. 3) formed in a central portion thereof, lever switch-mounting portions 13 and 15 (see FIG. 2) formed respectively in opposite sides thereof, and a control unit-mounting portion 17, and the body 3 has bus bars 19 for transmitting signals and electric current, the bus bars 19 being formed in the body 3 by insert molding. The bus bars 19 are arranged concentrically arcuately around the steering shaft insertion portion 11, and ends of part of the bus bars 19 serve as lever switch connection terminals 21 and 23 of the lever switch-mounting portions 13 and 15. The bus bars 19 project into the control unit-mounting portion 17, and serve as connection bars 25 which are connected to connection terminals of the control unit 9, and the various switch signals are transmitted to the control circuit on a board through the bus bars 19. Reference numeral 27 denotes a cover for covering the control unit 9.
In the above conventional combination switch 1, however, the bus bars 19 are in the form of a complicated arcuate circuit, to which the units, spaced from each other in the direction of the circumference of the steering shaft insertion portion 11, are formed in the body 3 by insert molding, and therefore there has been encountered a problem that this combination switch is costly.
And besides, the bus bars 19 are formed integrally in the body 3 by insert molding, and also the units, including the control unit 9 and a steering angle sensor, must be mounted directly on the body 3, and therefore the body 3 must have mounting spaces for these members, and as a result the configuration of the body is complicated, and also it is difficult to combine the units into a preassembly, and therefore the time and labor, required for the assembling operation, could not be reduced.